1. Field of the Invention
The present invention relates generally to payload delivery systems, and more specifically, to a guided parafoil system delivering lightweight payloads.
2. Background of the Invention
Chemical sensors, electronic sensing devices, as well as other lightweight packages often must be delivered via airdrop to a detection zone. In many cases, such as a possible hazardous area, the only practical way to deliver the sensor package is via aerial delivery. However, unguided airdrop of packages, particularly lightweight packages, is subject to drift error that may land the payload far from the desired drop location.
Guidance systems have been employed in delivery systems for large payloads (often weighing over several tons), and the added cost of the guidance system as well as the added weight of the power supplies, guidance computers, and control systems is typically justified by the size and cost of the payload. The guidance and control systems of the aforementioned delivery systems are typically very heavy, using either motorized propulsion or multi-axis guidance systems to provide sophisticated targeting capability.
Further, existing packages for uncontrolled drops are small with respect to the above-mentioned payload delivery systems. Canisters for deployment of electronic surveillance and countermeasures are standardized and it would be advantageous to provide a payload delivery system that is small enough to be deployed along with a payload in such a canister.
Therefore, it is desirable to provide a payload delivery system that is small, low cost and accurate. It would further be desirable to provide a payload delivery system that may be contained along with a small payload in a standardized canister.
The above objectives of providing a low cost, accurate and small payload delivery system for lightweight payloads are provided in a method and system that use a parafoil and a guidance system including a single motor for guidance control. The guidance system activates the motor to direct the parafoil in a horizontal direction perpendicular to a current direction of travel of the parafoil. The parafoil system is guided to a predetermined radius from the target and then is further guided in a downward spiral within a cylinder above the target until the descent is complete. Any deviations outside of the circular/spiral path are corrected by the guidance system in response to a deviation between a current position of the parafoil system and the cylinder. The parafoil is guided by a motor coupled to the guidance system that tensions a set of cables connected to the left or right side of the parafoil and loosens the other set of cables.
The foregoing and other objectives, features, and advantages of the invention will be apparent from the following, more particular, description of the preferred embodiment of the invention, as illustrated in the accompanying drawings.